This study investigated the effect of probiotics on growth performance, survival, and gut microbiota of Penaeus vannamei challenged with Vibrio parahaemolyticus IPNGS16. Shrimp were exposed to Bacillus thuringiensis IPNGSM1 and Candida parapsilosis Lt6 (BY, bacilli, 3×10⁶ CFU L^-1; yeast, 3×10⁶ CFU L^-1; yeast, 3 g kg^-1 feed) every fourth day for 30 days. On day 26, weight was determined, and samples for gut microbiota analysis were taken. Vibrio infection was performed on day 27. The software Shaman and MicrobiomeAnalyst were used to analyze the microbial sequences obtained from the Illumina platform. Additives did not affect growth, but survival significantly increased in shrimp treated with BY and challenged with V. parahaemolyticus. Predominant bacteria in shrimp gut belonged to Proteobacteria, Bacteroidetes, Vibrio, and Ruegeria. The bacterial community's diversity and composition did not change between treatment and control. In the treatment with BY, Vibrio showed decreased abundance, metabolism, and functional importance and showed negative interactions against Ruegeria, Pseudoalteromonas, Bacillus, and Roseobacter. Microbial additives increased survival in white shrimp but positively affected bacteria with probiotic potential and Vibrio negatively.